Caption: Orbit of a comet through the solar system, historical artwork. This illustration is from the book 'The use of globes', published by astronomer Thomas Wright (1711-1786) in London in 1740. The Sun is at centre, surrounded by the orbiting planets. Uranus, Neptune and Pluto had not yet been discovered. A comet (lower right) is shown entering the solar system, coming close to the sun and exiting again (top right). The four seasons are depicted around the edge of the illustration. Thomas Wright was a self-taught astronomer from Durham, England.